Who said innovation in mobile hardware is dead? For many smartphone makers, updating their flagship device is chiefly a matter of adding more health-related sensors. Yota, a new entrant to the mobile market, is hoping to carve out a niche with a very different take on hardware.

Yota's first device, the eponymous Yotaphone, was launched at the Mobile World Congress trade show last year and is now available in major European markets and Russia, Yota's home market.

On the surface, it might not look too special — there's a 4.3-inch screen, a front facing one-megapixel camera, and a sleek black casing that reminds you of a million and one other handsets out there right now.

But flip the Yotaphone over, and things start to get interesting.

(Image: Jo Best/ZDNet)

As well as the screen on the front, the Yotaphone has a second e-ink display on the back.

Like the front screen, it's 4.3inches; unlike the front screen, it's not multitouch — it's controlled by a touch strip at the bottom of the device — and it's purely black and white.

While the second screen shows updates, such as message notifications, it can also be used to 'pin' items to the back of the device, like this wallpaper, one of a number of animal themed wallpapers supplied with the device. If pugs aren't your thing, you can pin another image of your choice instead, using the camera, or just a screengrab.

By swiping down on the front of the device with two fingers, you can transfer what's on the front screen to the back display.

As it's an e-ink screen, its battery consumption is far less than the front-facing colour screen, so pinning something you need to frequently refer to — a map, for example — to the back can save you your battery from a pounding.

There are other times when using the back screen makes more sense – for example, pinning your boarding pass to the back screen means you can keep the ticket visible while you wait for your plane, even if your phone's battery is close to zero. It's also useful if you want to spend some time reading a book but without punishing your battery by doing so on the colour screen.

The screen resolution, 360x640, means the back screen isn't great for detail, but the front screen's 720x1280 is a slightly more perky affair.

Unfortunately, despite borrowing its second screen tech from e-book readers, the Yotaphone falls down when it comes to e-reading — the e-book apps you find on the Google Play store don't work with the back screen, for example.

For reading on the e-ink screen, the device comes with Yota's own Bookmate app. Its book-reading experience is pretty good, but the black and white screen does tend to have a habit of ghosting, meaning the previous image on the phone shows through on its current one — text from a book tends to show up faintly through the wallpaper, for example.

While there are a handful of Yota-made apps on the device that show what the second screen can be used for, expect more in the future: the company has released an SDK and is hoping others will take advantage of it to build their own apps involving the back display.

One of Yota's own additions is the rather sweet screen above: when the rear-facing camera is used, the second screen reminds users to smile.

It's not an earth-shatteringly useful piece of functionality, but it shows that the second screen can be put to rather clever uses, more of which will hopefully emerge in now the SDK is available.

Another inclusion on the second-generation device that should go some way to remedying the problems with its predecessor is the inclusion of a colour, multitouch screen.

The current non-touch screen has its niggles. For example, if you've pinned a map to the back screen and you need to reposition it, you'll need to flip over to the front display, adjust the map, and repin it. It's a similar story for the notifications – while the Yotaphone's back screen will show you when you've got a missed call or text message, to open it or respond, you'll need to head back to the front of the handset.

Zoom or scroll functionality would be a welcome addition here — the touch panel control used for the second screen is handy for turning a page, but not much more than that.

The phone also comes with an older version of Android, Jelly Bean.

The device is available in Russia, Belarus, Germany, Austria, France, Spain, the UK, Italy, Portugal, Poland, Denmark, Finland and Sweden for around €499 or £419.

It's a fairly high price considering the specs onboard – for a device that makes a lot of the battery-saving capabilities of the second screen, it's got a surprisingly low 1,800mAh battery; the camera is decent, but struggles with zoom; and the touch panels under both the front and back displays can be unresponsive.

The Yotaphone is a really interesting device, but it feels like it should have had more time in the oven. Reports of the prototype second-generation device, shown off at this year's Mobile World Congress, indicate that most of these flaws have been fixed.

With these gripes removed, the second generation Yotaphone is likely to be a far more compelling device, and one that shows there's still further room for innovation in the hardware — a lesson it would be great to see other, larger manufacturers learning too.

Who said innovation in mobile hardware is dead? For many smartphone makers, updating their flagship device is chiefly a matter of adding more health-related sensors. Yota, a new entrant to the mobile market, is hoping to carve out a niche with a very different take on hardware.

Yota's first device, the eponymous Yotaphone, was launched at the Mobile World Congress trade show last year and is now available in major European markets and Russia, Yota's home market.

On the surface, it might not look too special — there's a 4.3-inch screen, a front facing one-megapixel camera, and a sleek black casing that reminds you of a million and one other handsets out there right now.